^Again, excellent points, Sci
. The Gorn in particular have had mostly friendly relations with the Federation as far as we can tell. They had a violent first contact due to a misunderstanding, with the Gorn acting to defend themselves against what they believed were invaders. After that, though, relations seemed to go pretty well. They must have, since the Gorn actually ceded
the Cestus system to the Federation at some point. If they were a hostile power, there's no way that would've happened (since the UFP wouldn't engage in territorial conquest). The one instance of conflict we've seen since "Arena" was in The Gorn Crisis
, but that was with a militant faction that assassinated the sitting regime and was then defeated by Picard. If anything, the Gorn are indebted to the Federation for that.
As for the others, just because we've seen periods of conflict in the past doesn't mean those nations are defined solely by enmity. Look at real history. Over the course of its existence, the United States has at various times been at war with Great Britain, France, Mexico, the Philippines, Germany, Italy, Japan, and other states that are now our allies.